Ephemerythus pictus Gillies 1960

Kluge, Nikita J. & Novikova, Eugenia A., 2017, Revision of Ephemerythus Gillies 1960 (Ephemeroptera: Tricorythidae), Zootaxa 4347 (1), pp. 31-55 : 44-52

Ephemerythus pictus Gillies 1960

( FIGS 3–8 , 39–87 )

«Nymph of Ephemerellidae (genuS uncertain)»: KimminS 1956: 874 (larVa); Ephemerythus pictus Gillies 1960: 36 (♂ & ♀ imago);

Ephemerythus kiboensis GillieS 1960: 37 (♂ & ♀ imago), syn. n.;

« Ephemerythus ? kiboensis »: Demoulin 1965: 109, Fig. 11 (larVa);

« Ephemerythus ? pictus »: Demoulin 1965: 109, Fig. 12 (larVa);

genuS Limnokijara JacobuS & McCafferty 2006: 77 (larVa, imago) (Synonymized With genuS Ephemerythus by Kluge 2010a); Ephemerythus Sp. T : Kluge 2010a: 29 (larVa).

Material. TANZANIA, MbEyA REGION, LIvINGSTONE MOuNTAINS: RIvER MWALALO (TRIbuTARy Of LAkE NyASA) NEAR Matema , 9°29'S, 34°02'E, 6–14.VIII.2016, coll. N. Kluge & L. Sheyko: 1 L-S-I ♂, 1 L/S ♂, 1 L/S ♀; river Lufurio uPSTREAm TAPIO BRIDGE (15 km NW MATEmA) , 9°24'S, 33°55'E, 14.VIII.2016, cOLL. N. KLuGE: 1 LARvA. KILImANjARO REGION, KILImANjARO MOuNTAIN : MOSHI, 22.VIII.2017 cOLL. N. KLuGE & L. SHEukO: 1 LARvA; bASIN Of RIvER ONA IN Marangu, 13.X.1958, coll. M.T. Gillies (Q189-191) : 4 I ♂; the same locality , 23–27.VIII.2017, coll. N. Kluge & L. SHEukO: 1 L-S/I♂, 10 LARvAE. MOROGORO REGION, ULuGuRu MOuNTAINS: RIvER MOROGORO IN MOROGORO, 31.VII.2017, cOLL. N. KLuGE & L. SHEukO: 2 LARvAE; bASIN Of RIvER Ruvu NEAR KINOLE , 6°54'S, 37°45'E, 27–30.VII.2017, cOLL. N. KLuGE & L. SHEukO: 1 L-S-I♀, 2 L-S♀, 72 LARvAE. TANGA REGION, USAmbARA MOuNTAINS, RIvER SIGI NEAR AmANI, 5°06'S, 38°38'E, 19.VIII–2.IX.2016, coll. N. Kluge & L. Sheyko: 1 L-S/I ♂, 1 L-S-I ♀, 2 L-S ♀, 33 larvae; same LOcALITy, buT 5.VI.1961, cOLL. M.T. GILLIES: 1 LARvA.

Descriptions. Larva. STRUCTURE. BITING EDGE Of mAXILLA RELATIvELy WIDE: INNER-DORSAL ROW, bESIDES TWO DENTISETAE, WITH 5–6 SETAE PROXImAD Of PROXImAL DENTISETA; INNER-vENTRAL ROW cONSISTING Of 5–6 SETAE; APIcAL TufT Of LONG SETAE cONSISTING Of 12–14 vERy DENSE, ARcHED ROWS ( FIGS 46 , 51 ; KImmINS 1956: FIG. 9c ; DEmOuLIN 1965: FIG. 11f ; 1981: PL. XIf). FEmORA WIDE; STOuT SPATuLATE SETAE SHORT, ON fORE fEmuR fORmING NEARLy REGuLAR TRANSvERSE ROW ( FIGS 39–41 ; KImmINS 1956: FIG. 8 ; DEmOuLIN 1965: FIG. 11A ; 1981: PL. XIA). FORE TIbIA WITH POINTED PEcTINATE SETAE ON INNER SIDE AND LONGITuDINAL ROW Of STOuT bLuNT SETAE ON ANTERIOR SIDE, WITHOuT STOuT SETAE ON POSTERIOR SIDE; mIDDLE AND HIND TIbIAE WITH POINTED PEcTINATE SETAE ON INNER SIDE AND TWO LONGITuDINAL ROWS Of STOuT bLuNT SETAE ( AS IN E. niger – KLuGE 2010A: FIGS 16, 17 ). HIND PROTOPTERA PRESENT bOTH IN mALE AND fEmALE ( FIGS 5, 8 , 61, 67 ). AbDOmINAL TERGA AND STERNA WITH SPARSE SImPLE SETAE; bESIDES THIS, STERNA AND LATERAL AREAS Of TERGA WITH NumEROuS LARGER SOckETS ( FIGS 47–50 ). TERGALIuS V WITHOuT vENTRAL LObE; TERGALIuS VI AbSENT ( FIGS 42–45 ).

CUTICLE COLORATION. NEARLy uNIcOLOR, OcHER OR bROWNISH.

HYPODERMAL COLORATION. HEAD AND THORAX WITH vARIAbLE mAcuLATION; fEmORA WITH ONE OR TWO DIffuSE, bROWN cROSS bANDS; TIbIAE uNIcOLOR, WITHOuT cROSS bANDS ( FIGS 39–41 ). HyPODERmAL cOLORATION Of fORE PROTOPTERA DIffERING AmONG SEXES AND INSTARS: IN mALE LARvA cOSTAL, SubcOSTAL AND PART Of RADIAL fIELDS cOLORED by DARk GRAy , OTHER mEmbRANE NON-cOLORED; IN mALE LARvA Of LAST INSTAR ALL vEINS (LONGITuDINAL, cROSS AND INTERcALARy) ALSO cOLORED by DARk GRAy ( FIGS 7 , 40 ) ; IN mALE LARvA Of PREvIOuS INSTARS vEINS NOT cOLORED ( FIGS 6 , 39 ) . IN fEmALE LARvA Of ALL INSTARS WHOLE mEmbRANE cOLORED by DARk GRAy, ALL vEINS (LONGITuDINAL, cROSS AND INTERcALARy) NON-cOLORED ( FIGS 3, 4 , 41 ). AbDOmINAL TERGA SImILAR TO THAT Of ImAGO (cOmPARE mALE LARvAE ON FIGS 39–40 AND mALE ImAGO ON FIG. 63 , fEmALE LARvA ON FIG. 41 AND fEmALE ImAGO ON FIG. 64 ).

Subimago. CuTIcLE PARTLy cOLORLESS, PARTLy bROWN, mIcROTRIcHIAE DARk bROWN; cuTIcLE Of mESONOTum WITH cERTAIN AREAS cONTRASTINGLy cOLORED WITH DARk bROWN, WITH cONTRASTING cOLORLESS TRANSvERSE bAND AND LONGITuDINAL mEDIAN bAND ( FIG. 73 ); fEmORA Of ALL LEGS WITH bROWN bANDS ALONG INNER AND OuTER mARGINS; TIbIA Of HIND LEG WITH bROWN bAND ALONG OuTER mARGIN ( FIG. 69 ). WING WITH DARk bROWN RING AT bASE Of EAcH mIcROTRIcHION ( FIG. 72 ). CuTIcLE Of AbDOmEN LIGHT bROWN, WITH SmALL cOLORLESS AREAS; cuTIcLE Of cAuDALII ENTIRELy cOLORLESS ( FIG. 70 ). HyPODERmAL cOLORATION AS IN ImAGO. PENIS AS IN ImAGO, WITH POINTED ScLEROTIzED APIcES Of PAIRED LObES ( FIG. 71 ; cOmPARE WITH FIG. 77 ).

Male imago. COLORATION AS IN FIGS 58 , 62 , 63 . FORE WING WITH cOSTAL AND SubcOSTAL fIELDS DIffuSELy DARkENED by GRAy-bROWN AND WITH DIffuSE, GRAy-bROWN mAcuLA NEAR bASE; OTHER mEmbRANE cOLORLESS ( FIG. 58 ). HIND WING DIffuSELy DARkENED by GRAy-bROWN IN PROXImAL HALf, DISTAL PART Of mEmbRANE cOLORLESS ( FIGS 59 , 60 ). AbDOmINAL TERGum I ENTIRELy GRAy , OTHER TERGA PARTLy GRAy; LATERAL AREAS Of TERGA fROm II OR III TO VI OR VII NON-PIGmENTED; mEDIAN AREAS Of THESE TERGA EITHER ENTIRELy GRAy ( FIG. 62 ), OR WITH cONTRASTING NON-PIGmENTED mEDIAN PART ( FIG. 63 ); POSTERIOR TERGA AT mOST PART GRAy (SEE «COmmENTS» bELOW). PENIS WELL-ScLEROTIzED, bROWNISH-yELLOW; APIcES Of PAIRED PENIS LObES, SuRROuNDING GENITAL OPENING, HEAvILy ScLEROTIzED AND POINTED ( FIGS 53 , 77 ; GILLIES 1960: FIG. 11 ; KLuGE 2010A: FIG. 27 ).

Female imago. COLORATION AS IN FIG. 64 . HIND WING PRESENT, WITH PROXImAL PART (INcLuDING cOSTAL PROcESS) AS LARGE AS IN mALE, DISTAL PART (DISTAD Of cOSTAL PROcESS) SHORTER THAN IN mALE ( FIG. 66 ). FORE AND HIND WINGS ENTIRELy DARkENED WITH GRAy-bROWN. AbDOmEN NEARLy ENTIRELy DARk GRAy-bROWN.

Egg ( FIGS 78–84 ). AS cHARAcTERIzED fOR Ephemerythus (SEE AbOvE) ; LENGTH (WITHOuT cAP AND TAIL) AbOuT 0.2 mm; TAIL LENGTH 0.05 mm. TAIL cONSISTING Of 4 STOuT cONIc PROcESSES; EAcH PROcESS APIcALLy POINTED, uSuALLy WITH 2 SubAPIcAL DENTIcLES by SIDES ( FIG. 79 ); PROcESSES EITHER fREE ( FIG. 81 ), OR fuSED TO ONE ANOTHER uP TO SubAPIcAL DENTIcLES by mEANS Of THIN WALLS ( FIG. 83 ).

Size. FORE WING LENGTH Of mALE 5.5– 6 mm, Of fEmALE 5.5– 7 mm.

Comments. BASED ON AbDOmINAL cOLORATION Of mALE ImAGOES, GILLIES (1960) DEScRIbED E. pictus fROm AmANI (USAmbARA MOuNTAINS) AND E. kiboensis fROm MARANGu (KILImANDjARO MOuNTAIN) AS TWO DIffERENT SPEcIES. AccORDING TO OuR ObSERvATION, HyPODERmAL cOLORATION Of AbDOmEN Of mAILS IS PEcuLIAR fOR cERTAIN POPuLATIONS: mALE LARvAE, SubImAGOES AND ImAGOES fROm USAmbARA MOuNTAINS AND ULuGuRu MOuNTAINS HAvE LIGHT mEDIAN AREA ON SOmE AbDOmINAL TERGA (cOLORATION DEScRIbED fOR E. pictus ), WHILE mALE LARvAE, SubImAGOES AND ImAGOES fROm KILImANDjARO AND LIvINGSTONE MOuNTAINS HAvE AbDOmINAL TERGA uNIfORmLy DARk (cOLORATION DEScRIbED fOR E. kiboensis ). OuR EXAmINATION Of THE REARED mALE ImAGOES Of bOTH THESE fORmS ALLOWS TO cONcLuDE THAT THESE fORmS bELONG TO ONE SPEcIES. THE REARED mALE ImAGOES fROm AmANI (USAmbARA MOuNTAINS), MARANGu (KILImANDjARO) AND MATEmA (LIvINGSTONE MOuNTAINS) HAvE THE SAmE STRucTuRE Of LARvAE, SubImAGOES AND ImAGOES (AS DEScRIbED AbOvE) AND DIffER ONLy by cOLORATION Of mALE AbDOmINAL TERGA; EGGS EXTRAcTED fROm fEmALES Of THE SAmE POPuLATIONS (THE REARED fEmALE ImAGO fROm AmANI AND THE fEmALE LARvA fROm MATEmA) ALSO HAvE THE SAmE STRucTuRE ( FIGS 78–84 ). BESIDES cOLORATION, GILLIES (1960) REPORTED DIffERENcES IN THE ARRANGEmENT Of SPINE-LIkE SETAE ON THE GONOSTyLI; AccORDING TO HIm, IN E. pictus «SPINES ON bASAL SEGmENT ScANTy, LARGELy cONfINED TO DISTAL SWELLING» AND IN E. kiboensis «bASAL SEGmENT WITH NumEROuS SHARP SPINES ON INNER SuRfAcE EXTENDING ALmOST TO ITS bASE». AcTuALLy, THIS cHARAcTER DOES NOT DISTINGuISH E. pictus AND E. kiboensis fROm ONE ANOTHER ( FIGS 54–57 ). BASED ON THIS, WE PROPOSE A NEW SyNONymy E. pictus = E. kiboensis syn. n.

DEmOuLIN (1965) DEScRIbED AND fIGuRED LARvAE PRESumAbLy AScRIbED TO E. kiboensis (LARvAE fROm MARANGu IN KILImANDjARO) AND TO E. pictus (LARvAE fROm RIvER MGETA NEAR BuNDukI IN ULuGuRu MOuNTAINS). HIS fIGuRE TITLED « Ephemerythus ? kiboensis GILLIES , LARvE», ADEquATELy SHOWS cHARAcTERS Of yOuNG LARvA Of THIS SPEcIES ( FIG. 85 ). BuT HIS fIGuRE TITLED « Ephemerythus ? pictus GILLIES , LARvE», LOOkS quITE DIffERENT: THERE IS SHOWN A mATuRE mALE LARvA, WHOSE PRONOTum HAS uNuSuAL SHAPE, WITH POSTERIOR mARGIN ARcHED AND LATERO-POSTERIOR ANGLES GREATLy STRETcHED bAckWARD ( FIG. 86 ). BASED ON THIS fIGuRE, THE SHAPE Of PRONOTum WAS REPORTED AS A SPEcIES-SPEcIfIc cHARAcTER WITHIN Ephemerythus (KLuGE 2010A: TAbLE 1). TO INvESTIGATE THIS SPEcIES, N. KLuGE AND L. SHEykO mADE A SPEcIAL cOLLEcTING TRIP TO BuNDukI IN 2017. DuRING THIS TRIP, NO ONE LARvA Of Ephemerythus WAS fOuND IN THE RIvER MGETA NEAR BuNDukI, buT LARvAE Of Ephemerythus WERE AbuNDANT IN THE NEIGHbORING bASIN Of RIvER Ruvu IN THE SAmE mOuNTAINS. ALL LARvAE Of Ephemerythus fROm THIS AREA bELONG TO E. pictus AND HAvE uSuAL SHAPE Of THORAcIc TERGA, I. E., WITH STRAIGHT TRANSvERSE SuTuRE SEPARATING PRONOTum fROm mESONOTum. WHEN mATuRE LARvA bEcOmES READy TO mOLT TO SubImAGO, ITS INTENSIvELy PIGmENTED SubImAGINAL NOTum IS WELL vISIbLE THROuGH ITS LIGHT AND TRANSLucENT LARvAL cuTIcLE, THAT mAkES ILLuSION Of THE uNuSuAL SHAPE Of PRONOTum ( FIG. 87 ). PRObAbLy, THIS ILLuSION WAS A REASON Of THE ERROR IN THE DEmOuLIN'S fIGuRE. THuS, ALL LARvAE Of Ephemerythus REPORTED by DEmOuLIN (1965) fROm EAST AfRIcA (bOTH fROm KILImANDjARO AND fROm ULuGuRu MOuNTAINS), bELONG TO ONE SPEcIES, E. pictus (= E. kiboensis ).

JAcObuS & McCAffERTy (2006) ESTAbLISHED THE GENuS Limnokijara JAcObuS & McCAffERTy 2006 TO bE cOmPRISED Of TWO SPEcIES, L. picta AND L. kiboensis . THE DIAGNOSIS Of THE GENuS Limnokijara IN SucH SENSE IS THEREfORE IDENTIcAL TO THE SPEcIES E. pictus (= E. kiboensis ).

Figures

FIGURES 1 – 8. Hypodermal coloration of protoptera. 1 – 2, Ephemerythus niger, female larVa of laSt inStar: 1, hypoderm extracted from protopteron; 2, protopteron With cuticle and hypoderm. 3 – 8, Ephemerythus pictus: 3, female larVa of penultimate inStar; 4, female larVa of laSt inStar; 5, itS hind protopteron; 6, male larVa of penultimate inStar; 7, male larVa of laSt inStar; 8, itS hind protopteron.

FIGURES 39 – 46. Ephemerythus pictus from Amani. 39, male larVa of penultimate inStar; 40, male larVa of laSt inStar; 41, female larVa of laSt inStar; 42 – 45, tergalii of II – V abdominal SegmentS; 46, maxilla.

FIGURES 47 – 50. Ephemerythus pictus, abdominal Sternum VIII of larVa.

FIGURES 51 – 57. Ephemerythus pictus. 51, apex of maxilla (dorSal VieW, dentiSetae dotted; moSt part of Setae of apical tuft not ShoWn, area occupied by them ShoWn by dotted line, their baSeS on Ventral Side ShoWn by interrupted lineS). 52, hind margin of abdominal Sternum IX of laSt inStar male larVa, dorSal VieW (deVeloping Subimaginal genitalS ShoWn by interrupted lineS); 53, peniS of male imago (Ventral VieW, gonoductS ShoWn by dotted lineS); 54 – 57, firSt SegmentS of Subimaginal gonoStyli, dorSal VieW (Setae on Ventral Side ShoWn by interrupted lineS): 54 – 55, left and right gonoStyli of reared Specimen from Amani (the Same aS in Fig. 63); 56 – 57, left and right gonoStyli of reared Specimen from Matema (the Same aS in FigS 58 – 62, 70 – 71, 74 – 77). AbbreViationS: dS 1, diStal dentiSeta; dS 2, proximal dentiSeta; i-d, Setae of inner-dorSal roW.

FIGURES 58 – 67. Ephemerythus pictus. 58 – 62, reared male imago from Matema: 58, lateral VieW; 59, itS hind Wing at the Same magnification; 60, hind Wing; 61, larVal hind protopteron at the Same magnification; 62, abdomen. 63, abdomen of reared male imago from Amani (With genitalS coVered by Subimaginal exuViae). 64 – 67, reared female imago from Amani: 64, lateral VieW; 65, itS hind Wing at the Same magnification; 66, hind Wing; 67, larVal hind protopteron at the Same magnification.

FIGURES 68 – 77. Ephemerythus pictus. 68 – 73, Subimaginal exuViae: 68, tarSuS; 69, hind leg; 70, abdomen of male; 71, apiceS of peniS; 72, Wing; 73, left half of meSonotum. 74 – 76, male imaginal genitalS With focuS on Styliger, gonoStyli and peniS; 77, peniS With focuS on dorSal Side.

FIGURES 78 – 84. Ephemerythus pictus, eggS. 78 – 79, 81 – 83, extracted from reared female imago from Amani; 80, 84, extracted from mature larVa from Matema.

FIGURES 85 – 87. VariouS draWingS of larVa of Ephemerythus pictus. 85, « Ephemerythus? kiboensis » (from Demoulin 1965: Fig. 11 a). 86, « Ephemerythus? pictus » (from Demoulin 1965: Fig. 12 a). 87, original draWing of mature male larVa from Uluguru MountainS (interrupted lineS ShoW outlineS of Subimaginal head and thorax ViSible through larVal cuticle).

FIGURES 9 – 13. LarVae of Ephemerythus niger: 9, apex of maxilla (Ventral VieW, dentiSetae dotted, moSt part of Setae of apical tuft not ShoWn, area occupied by them ShoWn by dotted line); 10, maxilla of pen-penultimate inStar With deVeloping maxilla of penultimate inStar (focuS on inner-dorSal roW); 11 – 13, female larVae of laSt inStar from Amani. AbbreViationS: dS 1, diStal dentiSeta; dS 2, proximal dentiSeta; i-d, Setae of inner-dorSal roW.

FIGURES 14 – 17. Ephemerythus niger: 14, 15, reared male and female imagoeS from Amani (Tanzania); 16, I – VIII abdominal SegmentS of reared male Subimago from RiVer IShaSha (Uganda); 17, the Same of male imago from Mfumbi (Tanzania).

FIGURES 27 – 31. Ephemerythus nigricolor Sp. n. 27, exuViae of left half of Subimaginal meSonotum; 28 – 29, female larVae of laSt inStar; 30, male imago (holotype); 31, itS hind Wing.